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TRI National Analysis

TSCA and TRI

The Toxic Substances Control Act (TSCA), as amended by the Frank R. Lautenberg Chemical Safety for the 21st Century Act, is the nation’s primary chemicals management law. Under TSCA, existing chemicals in commerce and new chemicals intended for use in commerce are reviewed for safety through a risk-based process with increased public transparency.

The three stages of EPA’s process for evaluating the safety of existing chemicals are prioritization, risk evaluation, and risk management. During both the prioritization and risk evaluation stages of the process, TRI serves as a source of information, as illustrated in the figure below.

TRI and TSCA

Prioritization. Approximately two-thirds of the chemicals identified in the 2014 update of the TSCA Work Plan are also included on the TRI list of chemicals. TRI is well suited to help inform prioritization of chemicals for risk evaluation because TRI data contain information on release quantities of TRI chemicals to air, water and land, and the locations of these releases, and are submitted annually. Note that designation as a TRI chemical by itself does not determine high or low priority for a chemical.

Risk evaluation. A TSCA risk evaluation of a chemical is a comprehensive evaluation of the risk the chemical poses to human health and the environment over the chemical’s life cycle. The conditions of use for the chemical are evaluated, which may include manufacturing and import, processing, use, and disposal. During risk evaluation, EPA is required to assess occupational exposure, as well as general population exposure, and exposure to ecological receptors that may be sensitive to the potential hazards posed by the chemical under review. The TRI is a useful source of information for assisting in estimating these exposures, as it contains release quantities of TRI chemicals to air, water, and land, the locations of these releases, as well as information on use and waste management practices that may lead to exposure.

EPA uses TRI data as an information source to estimate and analyze environmental releases from industrial uses of the chemical in the risk evaluation. The figure below provides an example of a water release assessment for a chemical throughout the multiple phases of its industrial life cycle. At each life cycle phase, both the number of sites and quantity released are determined based on the TRI data. The release assessment estimates the amount of the chemical entering the environment, which can subsequently be used to model exposures of general populations and environmental species for each condition of use. To complete the risk evaluation stage, EPA makes a risk determination stating whether a chemical substance presents an unreasonable risk to human health or the environment under its conditions of use.

Release Assessment for Perchloroethylene

Management. If EPA determines that a chemical presents an unreasonable risk to human health or the environment, EPA will evaluate options for mitigating the risks. EPA is required to implement, via regulation, restrictions on the manufacture, processing, distribution, use and/or disposal of the chemical to eliminate the unreasonable risk. EPA is given a range of risk management options under TSCA, including labeling, recordkeeping or notice requirements, actions to reduce human exposure or environmental release, or a ban of the chemical or of certain uses of the chemical. TRI data, such as on chemical use and pollution prevention, may be used to inform these risk management decisions.


This page was published in March 2019 and uses the 2017 TRI National Analysis dataset made public in TRI Explorer in October 2018.

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